Secrets of the first empire

So I cleared tot lfr and a bit of tot normal this week, and only after that I got this part of the legendary questline.
I looked up info on it and I never found the answer to my question.

So, if I cleared tot lfr before I got the quest this week, can I still get the Secrets of the empire for re running it? (I know I will not get any loot/bags)
I was in the same spot when I did toes and got my last sigil.... xD But the item still dropped from the Sha of fear when I re ran it.